Multimode Luminescence with Temperature and Energy Level Synergistic Dependence in Rare Earth Halide DPs for Advanced Multifunctional Applications.

Rare-earth halide double perovskites (DPs) have attracted extensive attention due to their excellent optoelectronic performance. However, the correlation between luminescence performance, crystal structure, and temperature, as well as the inherent energy transfer mechanism, is not well understood. Herein, Lanthanide ions (Ln3+: Nd3+ or Dy3+) as the co-dopants are incorporated into Sb3+ doped Cs2NaYbCl6 DPs to construct energy transfer (ET) models to reveal the effects of temperature and energy levels of rare earth on luminescence and ET. The different excited state structures of Sb3+-Ln3+ doped Cs2NaYbCl6 DPs at different temperatures and relative positions of energy levels of rare earth synergistically determine the physical processes of luminescence. These multi-mode luminescent materials exhibit good performance in anti-counterfeiting, NIR imaging, and temperature sensing. This work provides new physical insights into the effects of temperature and energy levels of rare earth on the energy transfer mechanism and related photophysical process.

A Wearable Sandwich Heterostructure Multimode Fiber Optic Microbend Sensor for Vital Signal Monitoring.

This work proposes a highly sensitive sandwich heterostructure multimode optical fiber microbend sensor for heart rate (HR), respiratory rate (RR), and ballistocardiography (BCG) monitoring, which is fabricated by combining a sandwich heterostructure multimode fiber Mach-Zehnder interferometer (SHMF-MZI) with a microbend deformer. The parameters of the SHMF-MZI sensor and the microbend deformer were analyzed and optimized in detail, and then the new encapsulated method of the wearable device was put forward. The proposed wearable sensor could greatly enhance the response to the HR signal. The performances for HR, RR, and BCG monitoring were as good as those of the medically approved commercial monitors. The sensor has the advantages of high sensitivity, easy fabrication, and good stability, providing the potential for application in the field of daily supervision and health monitoring.

Circularly Polarized Luminescence Induced by Hydrogen-Bonding Networks in a One-Dimensional Hybrid Manganese(II) Chloride.

Chiral hybrid metal halides hold great potential as circularly polarized luminescence light sources. Herein, we have obtained two enantiomeric pairs of one-dimensional hybrid chiral manganese(II) chloride single crystals, R/S-(3-methyl piperidine)MnCl3 (R/S-1) and R/S-(3-hydroxy piperidine)MnCl3 (R/S-2), crystallizing in the non-centrosymmetric space group P212121. In comparison to R/S-1, R/S-2 single crystals not only show red emission with near-unity photoluminescence quantum yield (PLQY) and high resistance to thermal quenching but also exhibit circularly polarized luminescence with an asymmetry factor (glum) of 2.5×10-3, which can be attributed to the enhanced crystal rigidity resulting from the hydrogen bonding networks between R/S-(3-hydroxy piperidine) cations and [MnCl6]4- chains. The circularly polarized luminescence activities originate from the asymmetric [MnCl6]4- luminophores induced by N-H⋅⋅⋅Cl hydrogen bonding with R/S-(3-hydroxy piperidine). Moreover, these samples demonstrate great application potential in circularly polarized light-emitting diodes and X-ray scintillators. This work shows a highly efficient photoluminescent Mn-based halide and offers a strategy for designing multifunctional chiral metal halides.

Loss of polarity protein Par3 in the intestinal epithelium promotes colitis-associated colorectal cancer progression by damaging tight junction assembly.

Partitioning defective 3 (Par3) is a polarity protein critical in establishing epithelial cell polarity and tight junctions (TJs). Impaired intestinal epithelial barrier integrity is closely associated with colitis-associated colorectal cancer (CRC) progression. According to the GEO and TCGA database analyses, we first observed that the expression of Par3 was reduced in CRC patients. To understand how Par3 is related to CRC, we investigated the role of Par3 in the development of CRC using an in vivo genetic approach. Our results show that the intestinal epithelium-specific PAR3 deletion mice demonstrated a more severe CRC phenotype in the context of azoxymethane/dextran sodium sulfate (AOM/DSS) treatment, with a corresponding increase in tumor number and inflammatory cytokines profile. Mechanistically, loss of Par3 disrupts the TJs of the intestinal epithelium and increases mucosal barrier permeability. The interaction of Par3 with ZO-1 prevents intramolecular interactions within ZO-1 protein and facilitates the binding of occludin to ZO-1, hence preserving TJs integrity. Our results suggest that Par3 deficiency permits pathogenic bacteria and their endotoxins to penetrate the intestinal submucosa and activate TLR4/MyD88/NF-κB signaling, promoting inflammation-driven CRC development and that Par3 may be a novel potential molecular marker for the diagnosis of early-stage CRC.

Performance improvement of Hf0.45Zr0.55Oxferroelectric field effect transistor memory with ultrathin Al-O bonds-modified InOxchannels.

Ferroelectric field effect transistor (FeFET) memories with hafnium zirconium oxide (HZO) ferroelectric gate dielectric and ultrathin InOxchannel exhibit promising applicability in monolithic three-dimensional (M3D) integrated chips. However, the inferior stability of the devices severely limits their applications. In this work, we studied the effect of single cycle of atomic-layer-deposited Al-O bonds repeatedly embedded into an ultrathin InOxchannel (∼2.8 nm) on the Hf0.45Zr0.55OxFeFET memory performance. Compared to the pure InOxchannel, three cycles of Al-O bonds modified InOxchannel (IAO-3) generates a much larger memory window (i.e. drain current ratio between the programmed and erased devices) under the same program conditions (+5.5 V/500 ns), especially after post-annealing at 325 °C for 180 s in O2(1238 versus 317). Meanwhile, the annealed IAO-3 FeFET memory also shows quite stable data retention up to 104s, and much more robust program/erase stabilities till 105cycles. This is because the modification of strong Al-O bonds stabilizes the oxygen vacancies and reduces the bulk trap density in the channel. Furthermore, it is indicated that the program and erase efficiencies increase gradually with reducing the channel length of the memory device. By demonstrating markedly improved performance of the HZO FeFET memory with the ultrathin IAO-3 channel, this work provides a promising device for M3D integratable logic and memory convergent systems.

Microfluidic Biosensor Based on Molybdenum Disulfide (MoS2) Modified Thin-Core Microfiber for Immune Detection of Toxoplasma gondii.

Toxoplasma gondii (T. gondii) is a zoonotic parasite that is widely distributed and seriously endangers public health and human health. Therefore, accurate and effective detection of T. gondii is crucial. This study proposes a microfluidic biosensor using a thin-core microfiber (TCMF) coated with molybdenum disulfide (MoS2) for immune detection of T. gondii. The single-mode fiber was fused with the thin-core fiber, and the TCMF was obtained by arc discharging and flame heating. In order to avoid interference and protect the sensing structure, the TCMF was encapsulated in the microfluidic chip. MoS2 and T. gondii antigen were modified on the surface of TCMF for the immune detection of T. gondii. Experimental results showed that the detection range of the proposed biosensor for T. gondii monoclonal antibody solutions was 1 pg/mL to 10 ng/mL with sensitivity of 3.358 nm/log(mg/mL); the detection of limit was calculated to be 87 fg/mL through the Langmuir model; the dissociation constant and the affinity constant were calculated to be about 5.79 × 10-13 M and 1.727 × 1014 M-1, respectively. The specificity and clinical characteristics of the biosensor was explored. The rabies virus, pseudorabies virus, and T. gondii serum were used to confirm the excellent specificity and clinical characteristics of the biosensor, indicating that the proposed biosensor has great application potential in the biomedical field.

Study on the Design and Performance of a Glove Based on the FBG Array for Hand Posture Sensing.

This study introduces a new wearable fiber-optic sensor glove. The glove utilizes a flexible material, polydimethylsiloxane (PDMS), and a silicone tube to encapsulate fiber Bragg gratings (FBGs). It is employed to enable the self-perception of hand posture, gesture recognition, and the prediction of grasping objects. The investigation employs the Support Vector Machine (SVM) approach for predicting grasping objects. The proposed fiber-optic sensor glove can concurrently monitor the motion of 14 hand joints comprising 5 metacarpophalangeal joints (MCP), 5 proximal interphalangeal joints (PIP), and 4 distal interphalangeal joints (DIP). To expand the measurement range of the sensors, a sinusoidal layout incorporates the FBG array into the glove. The experimental results indicate that the wearable sensing glove can track finger flexion within a range of 0° to 100°, with a modest minimum measurement error (Error) of 0.176° and a minimum standard deviation (SD) of 0.685°. Notably, the glove accurately detects hand gestures in real-time and even forecasts grasping actions. The fiber-optic smart glove technology proposed herein holds promising potential for industrial applications, including object grasping, 3D displays via virtual reality, and human-computer interaction.

Highly sensitive curvature sensor based on a sandwich multimode fiber Mach-Zehnder interferometer.

A highly sensitive optical fiber Mach-Zehnder interference curvature sensor based on MMF-GIMMF-MMF, which was made by sandwiching the graded-index multimode fiber (GIMMF) between two pieces of very short stepped-index multimode fibers (SIMMFs) spliced with input-single-mode fiber (SMF) and output-SMF, respectively, was proposed. The core diameter of the SIMMFs and GIMMF was 105 µm and 50 µm, respectively, and cladding diameter of them were both 125 µm. The sensing principle of the MMF-GIMMF- MMF sensors and the influences of structure parameters on the interference spectrum characteristics were theoretically analyzed in detail. Experimental results showed that when the length of the GIMMF was short enough (usually ≤ 10 mm), interference spectrum was induced by the interaction between the core modes and the low-order cladding modes due to the special structure of the designed Mach-Zehnder interferometer. Intensity of the interference valleys was highly sensitive to the applied bending but nearly independent of the surrounding temperature, on the contrary, the dip wavelength showed negligible sensitivity to the applied bending but relatively high temperature sensitivity. Thus, a temperature- independent curvature sensor could be realized by tracing the intensity variation of interference valley. In addition, different interference valley exhibited different intensity-based curvature sensitivity, providing more options for curvature sensing applications. Especially, total length of the sensor could be as short as 3 mm with length of GIMMF and SIMMFs only 1mm, the maximum curvature sensitivity could reach up to -78.75 dB/m-1 in the small curvature range of 0-2.36 m-1. Owing to its compact size, easy fabrication, good reproducibility and low cost, the proposed sensor is promising for bending-related high-precision engineering applications.

Weakening Ligand-Liquid Affinity to Suppress the Desorption of Surface-Passivated Ligands from Perovskite Nanocrystals.

The interfacial migration of surface-bound ligands highly affects the colloidal stability and optical quality of semiconductor nanocrystals, of which the underlying mechanism is not fully understood. Herein, colloidal CsPbBr3 perovskite nanocrystals (PNCs) with fragile dynamic equilibrium of ligands are taken as the examples to reveal the important role of balancing ligand-solid/solvent affinity in suppressing the desorption of ligands. As a micellar surfactant, glycyrrhizic acid (GA) with bulky hydrophobic and hydrophilic groups exhibits a relatively smaller diffusion coefficient (∼440 µm2/s in methanol) and weaker ligand-liquid affinity than that of conventional alkyl amine and carboxy ligands. Consequently, hydrophilic GA-passivated PNCs (PNCs-GA) show excellent colloidal stability in various polar solvents with dielectric constant ranging from 2.2 to 32.6 and efficient photoluminescence with a quantum yield of 85.3%. Due to the suppressed desorption of GA, the morphological and optical properties of PNCs-GA are well maintained after five rounds purification and two months long-term storage. At last, hydrophilic PNCs-GA are successfully patterned through inkjet- and screen-printing technology. These findings offer deep insights into the interfacial chemistry of colloidal NCs and provide a universal strategy for preparing high-quality hydrophilic PNCs.

Cladding mode characteristics simulation of an excessively tilted fiber grating coated with gold nanoshells.

The cladding mode characteristics simulation of an excessively tilted fiber grating (ExTFG) coated with gold nanoshells was conducted in this study. First, the effective refractive indices of the core and cladding mode before coating were obtained by solving the eigenvalue equation of the three-layer waveguide structure, and the coupling characteristics were briefly analyzed. Then HE1,m and EH1,m modes were selected as the research objects, and the spectral characteristics of ExTFG coated with gold nanoshells were simulated by the finite element method. The simulated refractive index sensitivity of HE1,29 and EH1,29 modes is 160.16 and 185.03 nm/RIU, respectively. Compared with the non-localized surface plasmon resonance (LSPR) effect, it increased by 10.76 nm/RIU (7.2%) and 19.53 nm/RIU (11.8%), respectively. Thus, the LSPR effect was verified to be beneficial to improve the refractive index sensitivity of ExTFG.

Optical Vernier sensor based on a cascaded tapered thin-core microfiber for highly sensitive refractive index sensing.

This study proposes a refractive index (RI) sensor using a cascaded tapered thin-core microfiber (TTCMF) based on the Vernier effect. The thin-core fiber was made into a TTCMF by arc discharging and flame heating and then sandwiched between two single-mode fibers (SMFs). The two structures with the same SMF-TTCMF-SMF but slightly different free spectral ranges (FSRs) were cascaded to generate the Vernier effect. The FSR varied with the taper parameters of TTCMF. The RI sensitivities of a single TTCMF sensor, series SMF-TTCMF-SMF sensor, and parallel SMF-TTCMF-SMF sensor were compared and analyzed. Using the Vernier effect in the RI measurement range from 1.3313 to 1.3392, a very high RI sensitivity of -15,053.411n m/R I U was obtained using the series SMF-TTCMF-SMF structure, and -16,723.243n m/R I U using the parallel structure, which were basically consistent with the simulation results. Compared with the RI sensitivity of the single TTCMF sensor, the RI sensitivities of series and parallel sensors were increased by 4.65 times and 5.16 times, respectively. In addition, in the temperature range from 35°C to 65°C, temperature sensitivities of -0.196n m/ ∘ C and -0.0489n m/ ∘ C were obtained using series and parallel structures, respectively; the corresponding temperature cross errors were 1.302×10-5 R I U/ ∘ C and 2.92×10-6 R I U/ ∘ C, respectively. Based on the advantages of high RI sensitivity, simple structure, low-temperature cross sensitivity, and convenient fabrication, the proposed sensors have great potential in biosensing fields.

Kinetic pathways of crystallization at the nanoscale.

Nucleation and growth are universally important in systems from the atomic to the micrometre scale as they dictate structural and functional attributes of crystals. However, at the nanoscale, the pathways towards crystallization have been largely unexplored owing to the challenge of resolving the motion of individual building blocks in a liquid medium. Here we address this gap by directly imaging the full transition of dispersed gold nanoprisms to a superlattice at the single-particle level. We utilize liquid-phase transmission electron microscopy at low dose rates to control nanoparticle interactions without affecting their motions. Combining particle tracking with Monte Carlo simulations, we reveal that positional ordering of the superlattice emerges from orientational disorder. This method allows us to measure parameters such as line tension and phase coordinates, charting the nonclassical nucleation pathway involving a dense, amorphous intermediate. We demonstrate the versatility of our approach via crystallization of different nanoparticles, pointing the way to more general applications.

Highly sensitive vibration sensor based on the dispersion turning point microfiber Mach-Zehnder interferometer.

In the present work, we introduced a highly sensitive vibration sensor, which is based on the dispersion turning point (DTP) microfiber Mach-Zehnder interferometer. The axial strain and vibration sensing characteristics of the microfiber Mach-Zehnder interferometer were investigated. First, we theoretically analyzed the spectrum evolution characteristics of the microfiber Mach-Zehnder interferometer caused by axial strain. Second, the microfiber with different diameters was fabricated using the electrode discharge and fused taper method, and the axial strain experiments were conducted; the maximum sensitivity of the DTP microfiber with a diameter of ∼2.2 µm reached -45.55 pm/µÉ› at ∼1550 nm. Finally, based on the axial strain principle of the microfiber, we designed a highly sensitive vibration sensor using a DTP microfiber integrated into a rectangular through-hole cantilever beam. The 30-3500 Hz vibration signal monitoring could be realized, the maximum signal-to-noise ratio (SNR) was ∼75 dB at 52 Hz, and the acceleration sensitivity reached as high as 0.764 V/g at 45Hz. These results suggested the high performance of the microfiber in axial strain and micro-vibration sensing fields.

Optic-fiber vibration sensor based on a reflected 81° tilted fiber grating integrated with a symmetrical flexible hinge.

An optic-fiber vibration sensor based on the reflected 81° tilted fiber grating (81° TFG) integrated with a symmetrical flexible hinge is proposed and experimentally demonstrated in this paper. The vibration sensor is composed of a symmetrical flexible hinge and a reflected 81° TFG, the ends of which are simply fixed on the upper surface of the mass. The theoretical model of the proposed vibration sensor is analyzed, by which the important parameters related to the resonant frequency of the sensor are simulated and discussed; then, the vibration sensing experiments are conducted. Experiment results show that TE/TM mode of the 81° TFG can provide the maximal acceleration sensitivity of 338.28 and 299.94 mV/g at 400 Hz in the flat area of the amplitude-frequency response (50-400 Hz), which is increased by 9.95 and 11.5 times as compared with the optical fiber cantilever beam structure, respectively. Further, the signal-to-noise ratio in the flat area (50-400 Hz) is about ∼66.275dB under the acceleration of 2 g, which is increased by ∼20dB. Furthermore, it can be used for detecting mechanical vibration of medium-high frequency ranging from 50 to 3500 Hz. The proposed 81° TFG vibration sensor has the characteristics of small volume, simple package, high acceleration sensitivity, and wide vibration signal response range, which will ensure it has broad application prospects in the field of mechanical vibration.

"Colloid-Atom Duality" in the Assembly Dynamics of Concave Gold Nanoarrows.

We use liquid-phase transmission electron microscopy (TEM) to study self-assembly dynamics of charged gold nanoarrows (GNAs), which reveal an unexpected "colloid-atom duality". On one hand, they assemble following the Derjaguin-Landau-Verwey-Overbeek (DLVO) theory for colloids when van der Waals attraction overruns slightly screened electrostatic repulsion. Due to concaveness in shape, GNAs adopt zipper motifs with lateral offset in their assembly matching with our modeling of inter-GNA interaction, which form into unconventional structures resembling degenerate crystals. On the other hand, further screening of electrostatic repulsion leads to merging of clusters assembled from GNAs, reminiscent of the coalescence growth mode in atomic crystals driven by minimization of surface energy, as we measure from the surface fluctuation of clusters. Liquid-phase TEM captures the initial formation of highly curved necks bridging the two clusters. Analysis of the real-time evolution of neck width illustrates the first-time observation of coalescence in colloidal assemblies facilitated by rapid surface diffusion of GNAs. We attribute the duality to the confluence of factors (e.g., nanoscale colloidal interaction, diffusional dynamics) that we access by liquid-phase TEM, taking turns to dominate at different conditions, which is potentially generic to the nanoscale. The atom aspect, in particular, can inspire utilization of atomic crystal synthesis strategies to encode structure and dynamics in nanoscale assembly.

Effects of Particle Size on Mg2+ Ion Intercalation into λ-MnO2 Cathode Materials.

An emergent theme in mono- and multivalent ion batteries is to utilize nanoparticles (NPs) as electrode materials based on the phenomenological observations that their short ion diffusion length and large electrode-electrolyte interface can lead to improved ion insertion kinetics compared to their bulk counterparts. However, the understanding of how the NP size fundamentally relates to their electrochemical behaviors (e.g., charge storage mechanism, phase transition associated with ion insertion) is still primitive. Here, we employ spinel λ-MnO2 particles as a model cathode material, which have effective Mg2+ ion intercalation but with their size effect poorly understood to investigate their operating mechanism via a suite of electrochemical and structural characterizations. We prepare two differently sized samples, the small nanoscopic λ-MnO2 particles (81 ± 25 nm) and big micron-sized ones (814 ± 207 nm) via postsynthesis size-selection. Analysis of the charge storage mechanisms shows that the stored charge from Mg2+ ion intercalation dominates in both systems and is ∼10 times higher in small particles than that in the big ones. From both X-ray diffraction and atomic-resolution scanning transmission electron microscopy imaging, we reveal a fundamental difference in phase transition of the differently sized particles during Mg2+ ion intercalation: the small NPs undergo a solid-solution-like phase transition which minimizes lattice mismatch and energy penalty for accommodating new phases, whereas the big particles follow conventional multiphase transformation. We show that this pathway difference is related to the improved electrochemical performance (e.g., rate capability, cycling performance) of small particles over the big ones which provides important insights in encoding within the particle dimension, that is, the single-phase transition pathway in high-performance electrode materials for multivalent ion batteries.

Tip-Patched Nanoprisms from Formation of Ligand Islands.

We apply the concept of "island formation" established for planar substrates, where ligands laterally cluster as they adsorb, to preparing nanoparticles (NPs) with precisely sized surface patches. Using gold triangular nanoprisms and 2-naphthalenethiols (2-NAT) as a prototypical system, we show that the preferential adsorption of 2-NAT on the prism tips leads to formation of tip patches. The patches are rendered visible for direct transmission electron microscopy and atomic force microscopy imaging upon attaching polystyrene-b-poly(acrylic acid). Using this method, the shape of patchy prisms is varied from small lobed, big lobed, trefoil, T-shaped to a reuleaux triangle by increasing the 2-NAT-to-prism concentration ratio. This trend matches with predictions of island formation as elucidated by our self-consistent field theory modeling, from which we exclude Langmuir adsorption. The tip-patched prisms assemble into unexpected twisted dimers due to the patch-patch interactions. We expect the island formation as a generalizable strategy to make patchy NPs of various shapes for emergent assemblies and applications.

Synergistic Surface Passivation of CH3 NH3 PbBr3 Perovskite Quantum Dots with Phosphonic Acid and (3-Aminopropyl)triethoxysilane.

CH3 NH3 PbBr3 perovskite quantum dots (PQDs) are synthesized by using four different linear alkyl phosphonic acids (PAs) in conjunction with (3-aminopropyl)triethoxysilane (APTES) as capping ligands. The resultant PQDs are characterized by means of XRD, TEM, Raman spectroscopy, FTIR spectroscopy, UV/Vis, photoluminescence (PL), time-resolved PL, and X-ray photoelectron spectroscopy (XPS). PA chain length is shown to control the PQD size (ca. 2.9-4.2 nm) and excitonic absorption band positions (λ=488-525 nm), with shorter chain lengths corresponding to smaller sizes and bluer absorptions. All samples show a high PL quantum yield (ca. 46-83 %) and high PL stability; this is indicative of a low density of band gap trap states and effective surface passivation. Stability is higher for smaller PQDs; this is attributed to better passivation due to better solubility and less steric hindrance of the shorter PA ligands. Based on the FTIR, Raman, and XPS results, it is proposed that Pb2+ and CH3 NH3 + surface defects are passivated by R-PO3 2- or R-PO2 (OH)- , whereas Br- surface defects are passivated by R-NH3 + moieties. This study establishes the combination of PA and APTES ligands as a highly effective dual passivation system for the synergistic passivation of multiple surface defects of PQDs through primarily ionic bonding.

Probing Anisotropic Surface Properties of Illite by Atomic Force Microscopy.

For the purpose of understanding the colloidal behaviors of illite in mineral processing, probing the surface charging property of illite is of great significance. This research explored the edge and basal surfaces of illite using an atomic force microscope (AFM). The interaction forces between Si/Si3N4 probes and illite edge/basal surfaces were measured, respectively, at different pH values in 10 mM KCl solutions. Theoretical Derjaguin-Landau-Verwey-Overbeek forces were matched up with the measured forces to derive the surface potentials of the two surfaces. On the illite basal surface, an attractive force occurred at pH 3.0, while repulsive forces dominated from pH 5.0 to 10.0. On the illite edge surface, a slight attractive force was also obtained at pH 3.0. However, the interaction changed into repulsion at pH 5.0, and this repulsive force increased gradually from pH 6.0 to 10.0. Illite basal and edge surfaces were both negatively charged, but the basal surface exhibited more negative charges than the edge surface from pH 3.0 to 10.0. Increasing solution pH from 3.0 to 10.0, there was no detection of the point of zero charge (PZC) of the illite basal surface; however, the PZC of the illite edge surface should have occurred at a pH slightly lower than 3.0. This is the first time that surface potentials of illite edge and basal surfaces were attained separately by direct force measurements. These findings provide insights into the colloidal behaviors of illite in mineral processing and oil sands extraction.

Age-related changes in neuroinflammation and prepulse inhibition in offspring of rats treated with Poly I:C in early gestation.

BACKGROUND: Maternal immune activation (MIA) during gestation can increase the later risk of schizophrenia in adult offspring. Neuroinflammation is believed to underlie this process. Postmortem brain studies have found changes in the neuroimmune systems of patients with schizophrenia. However, little is known about the dynamic changes in cerebral inflammation and behavior during the course of the disease. METHODS: Here, the prepulse inhibition (PPI) test was conducted in adolescent and adult Sprague-Dawley rats prenatally challenged with polyriboinosinic-polyribocytidylic acid (Poly I:C) on gestational day 9 to determine the behavioral trajectory triggered by early exposure to Poly I:C. Brain immune changes were determined in the prefrontal cortex (PFC) and hippocampus (HC) at both ages. The status of the microglia and astrocytes was determined with immunohistochemical staining. The levels of IL-6, IL-1ß, and TNF-α in both brain regions were evaluated with enzyme-linked immunosorbent assays. RESULTS: Disrupted PPI, the core phenotype of schizophrenia, only emerged in adulthood. Behavioral changes during puberty and adulthood were both accompanied by the activation of microglia (PFC and HC). Astrocytes were only activated at PN60. The levels of proinflammatory cytokines (IL-1ß, IL-6, and TNF-α) in the offspring of the Poly I:C-exposed mothers differed with brain region and time, with more cytokines elevated during periadolescence than during adulthood. CONCLUSIONS: Our findings indicate that immune activation emerged before symptom manifestation in the offspring of MIA rats. We conclude that early prenatal Poly I:C challenge can lead to age-related behavioral and neuroinflammatory changes. These data provide new insight into the neuroinflammatory and neuropathological mechanisms underlying the development of schizophrenia. They also suggest that periadolescence could be more important than adulthood in the prevention and treatment of schizophrenia.